1. Field of the Invention
This invention relates to a cassette assembly for manufacturing fluorescent lamps, which can effectively carry and handle a plurality of glass tubes for the fluorescent lamps, and more particularly, to a cassette assembly for manufacturing fluorescent lamps, which can allow inner walls of a plurality of glass tube for fluorescent lamps to be simultaneously coated, thereby improving the productivity.
2. Description of the Related Art
Generally, a fluorescent lamp is produced by coating fluorescent substance exciting ultraviolet rays on the inside wall of a thin long glass tube, injecting light emitting gas and mercury in the glass tube, and sealing the glass tube. According to the position of electrode installed at opposite ends of the glass tube, the fluorescent lamps are classified into a cold cathode fluorescent lamp (CCFL) and an external electrode fluorescent lamp (EEFL). The EEFL has better light quality, longer lifetime, and less electric consumption as compared with the CCFL. Also, the EEFL can be produced to a compact size. Therefore, the EEFL has been widely used as a backlight of a liquid crystal display (LCD).
A typical method of manufacturing the EEFL includes a process of coating fluorescent substance the inside wall of the glass tube, a process of calcinating the coated fluorescent substance, a process of injecting light emitting gas and mercury into the glass tube, a process of sealing opposite ends of the glass tube, and a process of forming electrodes on the opposite ends of the glass tube.
Among the processes described above, the coating process and the injecting process are conventionally conducted with 3-5 glass tubes inserted in holes formed along a circumferential edge of a disc-shaped stage rotating horizontally.
However, in the conventional method of manufacturing the fluorescent lamp, since the coating, injecting and sealing processes are performed in a state where the small number of glass tubes are loaded to the size limited disc-shaped stage, it is difficult to improve the productivity.
In addition, since each glass tube has to be connected or disconnected one by one to a chamber in every process of the manufacturing procedure, the manufacturing process is complicated and consequently time-consuming.
Obviously, when the glass tubes are individually loaded on the stage or connected to a chamber, it is difficult to handle a lot of glass tubes during the manufacturing process, and therefore the working efficiency and the productivity are further deteriorated.